It has previously been known to use stamping tools to form decorative patterns in concrete to provide the appearance of, for example, ashlar slate, cobblestone, fieldstone, brick, and the like hand-laid materials. There are numerous advantages to using concrete as opposed to hand-laid materials. Specifically, concrete provides a durable pattern at a considerably reduced cost. Also, hand-laid materials generally settle randomly causing a particular structure to have an uneven surface that is extremely unsightly and hazardous. Moreover, vegetation as well as other debris is commonly present between adjacent hand-laid materials. This is not only unsightly but can likely lead to extensive damage to the structure.
The following patent documents illustrate a variety of tools which have been used to form decorative patterns in concrete: U.S. Pat. Nos. 1,096,445; 3,887,293; 3,930,740; 4,131,406; 4,135,840; 4,231,677; 4,776,723; 4,798,364; 4,828,426; 4,838,728; Des. 282,623; and U.K. Patent application Nos. 2,214,211A; 2,176,826A; and 2,111,897A. The aforementioned patent documents generally illustrate two types of tools. The first type of tool forms decorative grout lines in concrete. However, these tools lack the capability to form texturized surfaces in the concrete to provide the authentic appearance of, for example, slate or other hand-laid materials.
The second type of tool forms both decorative grout lines as well as texturized surfaces in the concrete. The preferred embodiment of the present invention is directed to the latter type of tool. Previously known tools of this type are illustrated in U.S. Pat. No. 4,776,723; U.S. Pat. No. Des. 282,623 and U.K. Patent Application No. 2,111,897A. These tools have several disadvantages inherent thereto. The '897A patent tool lacks a memory, i.e. the tool includes a rigid core which would likely prevent the tool from assuming its original shape once deformed by an external source. Accordingly, the tool must be discarded if deformed.
The '723 patent tool includes a pair of straps which permit a laborer to transport it to a desired location. Each strap includes a par of ends which are simply placed in the elastomer during the molding process and allowed to harden. However, after prolonged use of this type of tool, it is likely that the straps will sever from the body of the tool due to the tenuous connection therebetween.
Additionally, it is desirable to uniformly distribute the weight of tools used to form grout lines as well as texturized surfaces over the entire area thereof. A tool so formed will avoid unintended and unsightly deformations in the concrete. However, it has not previously been possible to readily determine whether tools of this type have been so formed from a visual inspection thereof.